6 documents found, page 1 of 1
Unexpected seasonality in quantity and composition of Amazon rainforest air rea...
Nölscher, Anke C.; Yáñez-Serrano, Ana Maria; Wolff, Stefan; Araüjo, Alessandro Carioca de; Lavric, J. V.; Kesselmeier, Jürgen; Williams, Jonathan C.The hydroxyl radical (OH) removes most atmospheric pollutants from air. The loss frequency of OH radicals due to the combined effect of all gas-phase OH reactive species is a measureable quantity termed total OH reactivity. Here we present total OH reactivity observations in pristine Amazon rainforest air, as a function of season, time-of-day and height (0-80 m). Total OH reactivity is low during wet (10s-1) an...
The Amazon Tall Tower Observatory (ATTO): Overview of pilot measurements on eco...
Andreae, Meinrat O.; Acevedo, Otávio C.; Araüjo, Alessandro Carioca de; Artaxo, Paulo; Barbosa, Cybelli G.G.; Barbosa, H. M. J.; Brito, Joel F.The Amazon Basin plays key roles in the carbon and water cycles, climate change, atmospheric chemistry, and biodiversity. It has already been changed significantly by human activities, and more pervasive change is expected to occur in the coming decades. It is therefore essential to establish long-term measurement sites that provide a baseline record of present-day climatic, biogeochemical, and atmospheric cond...
Atmospheric mixing ratios of methyl ethyl ketone (2-butanone) in tropical, bore...
Yáñez-Serrano, Ana Maria; Nölscher, Anke C.; Bourtsoukidis, Efstratios; Derstroff, Bettina; Zannoni, Nora; Gros, Valérie; Lanza, Matteo; Brito, Joel F.Methyl ethyl ketone (MEK) enters the atmosphere following direct emission from vegetation and anthropogenic activities, as well as being produced by the gas-phase oxidation of volatile organic compounds (VOCs) such as n-butane. This study presents the first overview of ambient MEK measurements at six different locations, characteristic of forested, urban and marine environments. In order to understand better th...
Opposite OH reactivity and ozone cycles in the Amazon rainforest and megacity B...
Williams, Jonathan C.; Keßel, Stephan U.; Nölscher, Anke C.; Yang, Yudong; Lee, Yue; Yáñez-Serrano, Ana Maria; Wolff, Stefan; Kesselmeier, JürgenThe Amazon rainforest in Brazil and the megacity of Beijing in China are two of the most strongly contrasting habitats on Earth. In both locations, volatile chemicals are emitted into the atmosphere affecting the local atmospheric chemistry, air quality and ecosystem health. In this study, the total reactivity in air available for reaction with the atmosphere's primary oxidant the OH radical, has been measured ...
Monoterpene chemical speciation in a tropical rainforest:variation with season,...
Yáñez-Serrano, Ana Maria; Nölscher, Anke C.; Bourtsoukidis, Efstratios; Alves, Eliane Gomes; Ganzeveld, Laurens N.; Bonn, Boris; Wolff, StefanSpeciated monoterpene measurements in rainforest air are scarce, but they are essential for understanding the contribution of these compounds to the overall reactivity of volatile organic compound (VOC) emissions towards the main atmospheric oxidants, such as hydroxyl radicals (OH), ozone (O3) and nitrate radicals (NO3). In this study, we present the chemical speciation of gas-phase monoterpenes measured in the...
Diel and seasonal changes of biogenic volatile organic compounds within and abo...
Yáñez-Serrano, Ana Maria; Nölscher, Anke C.; Williams, Jonathan C.; Wolff, Stefan; Alves, Eliane Gomes; Martins, Giordane AugustoThe Amazonian rainforest is a large tropical ecosystem, which is one of the last pristine continental terrains. This ecosystem is ideally located for the study of diel and seasonal behaviour of biogenic volatile organic compounds (BVOCs) in the absence of local human interference. In this study, we report the first atmospheric BVOC measurements at the Amazonian Tall Tower Observatory (ATTO) site, located in cen...